Aquarium filter

ABSTRACT

An aquarium filter assembly is mounted to an aquarium tank and defines a water flow path therethrough from upstream to downstream from an inlet to an outlet. A replaceable filter element is mounted in a filter chamber.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority from ProvisionalU.S. Patent Application No. 60/791,830, filed Apr. 13, 2006. Thisapplication also claims the benefit of and priority from Italian PatentApplication No. PD2006A000367, filed Oct. 5, 2006, and European PatentApplication No. 07103798.0, filed Mar. 8, 2007.

BACKGROUND AND SUMMARY

The invention relates to aquarium filters and assemblies.

Aquarium filters and assemblies are known in the prior art. The presentinvention arose during continuing development efforts directed towardimproved product construction, performance and features.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an aquarium filter assembly mounted toan aquarium tank.

FIG. 2 is a perspective view of the aquarium filter assembly of FIG. 1,partially cut-away and with cover removed.

FIG. 2A is an enlarged view of a portion of FIG. 2 at line 2A-2A.

FIG. 3 is an exploded perspective view of the aquarium filter assemblyof FIG. 2.

FIG. 4 is an enlarged perspective view of a component of FIG. 3.

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4.

FIG. 6 is an enlarged view of a portion of FIG. 3 at line 6-6.

FIG. 7 is a top view of a component of FIG. 3.

FIG. 8 is a sectional view taken along line 8-8 of FIG. 7.

FIG. 9 is a sectional view taken along line 9-9 of FIG. 1.

FIG. 10 is an enlarged perspective view of a component of FIG. 3 from adifferent angle.

DETAILED DESCRIPTION

FIG. 1 shows an aquarium filter assembly 20 including a housing 22having mounting structure 24 for mounting to an aquarium tank 26. Thetank has an interior 28 holding aquarium water therein as shown at waterline 30, and has an exterior at 32. The tank has a sidewall 34 with atop 36. The housing has a removable top cover 38, FIG. 2, having ventopenings or slits 40. A filter cartridge 42 is provided in the housingand has an upstream face 44, FIG. 3, and a downstream face 46. Thehousing has an inlet 48 receiving dirty aquarium water as shown at arrow50 through inlet grate or screen 52, and has an outlet 54 returningclean filtered water to the tank, as shown at water flow 56 at arrow 58.The housing defines a water flow path therethrough from upstream todownstream from inlet 48 to outlet 54. A water pump 60 in the housing isat least partially submerged in the water in the tank and pumps wateralong the noted flow path by means of impeller 62 driven by electricmotor 64 connected to a source of electrical power by power cord 66 topump water from pumping chamber 68 upwardly through channel 70 as shownat arrow 72 in FIGS. 7, 9, to pump the water along the noted flow paththrough the housing. Housing 22 is an inverted U-shaped saddle having anupper bight 74, FIGS. 1-3, 9 at the top 36 of sidewall 34 of the tank,and having inner and outer legs 76 and 78, respectively, dependingdownwardly from bight 74. Inner leg 76 extends into the interior 28 oftank 26. Outer leg 78 extends along the exterior 32 of tank 26. Filtercartridge 42 is in outer leg 78. Water pump 60 is in inner leg 76. Motor60 is detachable from the housing at living hinge spring clip 61.

Housing 22 has a filter chamber 80, FIGS. 2, 3, 7, 9, receiving filtercartridge 42 therein. The filter cartridge divides filter chamber 80into a filter inlet plenum 82 receiving water from inlet 48, and afilter outlet plenum 84 delivering water to outlet 54. Upstream face 44of the filter cartridge faces filter inlet plenum 82. Downstream face 46of the filter cartridge faces filter outlet plenum 84. Housing 22 has asupply plenum 86 receiving water from water pump 60 through channel 70and passage 71, and supplying the water to filter inlet plenum 82.Supply plenum 86 has an overflow bypass passage 88, FIGS. 7, 9, 10,supplying water from supply plenum 86 to filter outlet plenum 84 andbypassing filter cartridge 42 in response to clogging of the filtercartridge causing a given rise in water level in housing 22. Supplyplenum 86 spans inner and outer legs 76 and 78. Housing 22 has a returnplenum 90, FIGS. 7, 9, 10, spanning inner and outer legs 74 and 78 andcrossing over the noted top 36 of sidewall 34 of aquarium tank 26 andreturning water from filter outlet plenum 84 to outlet 54. Water fromoverflow bypass passage 88 from supply plenum 86 joins with water infilter outlet plenum 84 and return plenum 90 downstream of downstreamface 46 of the filter cartridge. Supply plenum 86 has a cross-overportion 92, FIGS. 3, 7, directly above the top 36 of sidewall 34 of tank26. Return plenum 90 has a cross-over portion 94 directly above the top36 of sidewall 34 of tank 26. Cross-over portion 94 has a lower wall 96,FIGS. 3, 7, 9, 10, therealong. Cross-over portion 94 is laterallyadjacent cross-over portion 92, and there is a plenum sidewall 98therebetween. Plenum sidewall 98 extends from lower wall 96 ofcross-over portion 94 upwardly to overflow bypass passage 88 at the topof sidewall 98.

Filter chamber 80 and filter cartridge 42 have respective first andsecond coacting keyed detents 102 and 104, FIGS. 2, 2A, 3, 8, 9, matingwith each other to at least one of: a) orient and permit mounting offilter cartridge 42 in filter chamber 80 only with face 44 facing filterinlet plenum 82, and face 46 facing filter outlet plenum 84; and b)permitting mounting of only an authorized filter cartridge in filterchamber 80, namely a filter cartridge having a coacting keyed detent tomate with coacting keyed detent 102 of filter chamber 80. In oneembodiment, filter cartridge 42 includes a replaceable filter element106, FIG. 3, having the noted second detent 104. First and seconddetents 102 and 104 are aligned with each other and non-symmetricallydisposed in offset relation in filter chamber 80. In one preferred form,first detent 102 is provided by a standing rib extending from housing 22into filter chamber 80, and second detent 104 is provided by an alignedslot in the filter element receiving standing rib 102 in insertedrelation. In another embodiment, the filter element has an auxiliarydetent, as shown in dashed line at 108 in FIG. 3, spaced from detent 104and, upon 180° reversal of orientation of filter element 106, coactingand mating with detent 102 to permit orientation and mounting of filterelement 106 in filter chamber 80 in an alternate reversed orientationposition with face 44 facing filter outlet plenum 84 rather than filterinlet plenum 82, to permit reversal of orientation of filter element 106as desired. The orientation of filter element 106 is reversed byremoving it from holster 110, to be described, and rotating filterelement 106 180° about a vertical axis. If filter element 106 isreversible and can desirably or equivalently filter water flow in eitherdirection, then the inclusion of both detents or slots 104 and 108 ispreferred, to enable filter element 106 to be mounted in either of 180°opposite orientations. If filter element 106 has a preferredorientation, for example a differential gradient density filter where itis preferred that face 44 be facing upstream, then only a single detentor slot 104 is preferred, and detent or slot 108 is eliminated, suchthat filter element 106 can only be mounted and oriented in a singleorientation position, namely with face 44 facing upstream toward filterinlet plenum 82. In the two slot version: detents 102 and 104 arealigned with each other and non-symmetrically disposed in offsetrelation in filter chamber 80 when face 44 faces filter inlet plenum 82;and detents 102 and 108 are aligned with each other andnon-symmetrically disposed in offset relation in filter chamber 80 whenface 44 faces filter outlet plenum 84, upon reversal of filter element106. In one embodiment, as noted, detent 102 is provided by a standingrib extending from housing 22 into filter chamber 80, detent 104 isprovided by a first slot in filter element 106 aligned with andreceiving standing rib 102 in inserted relation when face 44 facesfilter inlet plenum 82, and auxiliary detent 108 is provided by a secondslot in the filter element aligned with and receiving standing rib 102in inserted relation when face 44 faces filter outlet plenum 84.

In one embodiment, filter cartridge 42 includes the noted replaceablefilter element 106 and may additionally include a holster 110, FIGS. 2,3. Replaceable filter element 106 is removably supported in holster 110and is slidable downwardly thereinto. Filter element 106 and holster 110have respective grip tabs 107 and 111. The holster has a detent 112aligned with detent 104 and coacting with and mating with detent 102.Detents 102, 104, 112 are aligned with each other and non-symmetricallydisposed in offset relation in filter chamber 80. In one embodiment,detent 102 is provided by the noted standing rib extending from housing22 into filter chamber 80, and detents 104 and 112 are provided byaligned slots receiving standing rib 102 in inserted relation. Auxiliarydetent 108 of filter element 106 is spaced from detent 104 and, upon180° reversal of filter element 106, detent 108 coacts and mates withdetent 102 and is aligned with detent 112 to permit orientation andmounting of filter element 106 in holster 110 in filter chamber 80 withface 44 facing filter outlet plenum 84, to permit reversal oforientation of filter element 106 as desired. As above, if filterelement 106 has a preferred orientation, then slot 108 is eliminated,which in turn permits orientation and mounting of filter element 106 inthe filter chamber 80 only with face 44 facing filter inlet plenum 82.If optional dual alternate orientation is desired, then slot 108 isprovided, and: detents 102, 104, 112 are aligned with each other andnon-symmetrically disposed in offset relation in filter chamber 80 whenface 44 faces filter inlet plenum 82; and detents 102, 108, 112 arealigned with each other and non-symmetrically disposed in offsetrelation in filter chamber 80 when face 44 faces filter outlet plenum84.

Filter element 106 and holster 110 engage each other in sliding relationalong distally opposite guide tracks 114 and 116, FIG. 3, enablingremoval of filter element 106 from holster 110. Holster 110 and filterchamber 80 engage each other in sliding relation along distally oppositeguide tracks 118 and 120, FIGS. 3, 7, 10, enabling removal of holster110 from filter chamber 80. Guide tracks 114 and 118 are adjacent andparallel to each other. Guide tracks 116 and 120 are adjacent andparallel to each other.

Housing 22 defines a water flow path therethrough from upstream todownstream from inlet 48 to outlet 54 as shown at arrows 50, 72, 122,124, 126, 128, 130, 132, 134, 58, including a flow path portion 136,FIGS. 7, 9, through the filter cartridge. Holster 110 has a plurality ofwater flow openings 138 therethrough, FIGS. 6, 8, providing water flowalong flow path portion 136. The holster has a plurality of biologicalreactant surface area protrusions 140 extending therefrom along flowpath portion 136 adjacent water flow openings 138. It is known in theprior art to provide biological filtration in aquariums by means ofsurfaces collecting beneficial bacteria to eliminate toxic ammonia andnitrites, in addition to the mechanical filtration provided by filterelement 106, and in addition to chemical filtration which may beprovided by filter element 106 additionally containing activated carbonto remove toxic impurities, odors, and discoloration. Filter element 106and holster 110 have an intermediate plenum 142 therebetween, FIGS. 2,7, 9. Intermediate plenum 142 is downstream of filter inlet plenum 82,and is upstream of filter outlet plenum 84. Holster 110 has a first face144 facing intermediate plenum 142, and has a second face 146 facingoppositely from first face 144. Biological reactant surface areaprotrusions 140 extend from one of such faces, preferably face 146.Holster 110 is preferably downstream of filter element 106, and face 146of the holster faces filter outlet plenum 84, and biological reactantsurface area protrusions 140 extend from face 146 into filter outletplenum 84.

In a further embodiment, the filter assembly housing outlet 54 has aremovable insert 150, FIGS. 3, 4, having a plurality of biologicalreactant surface area protrusions 152 along flow path portion 126, 128through outlet 54. Biological reactant surface area protrusions 152 areprovided by a plurality of canopies 153, namely a first row 154 of aplurality of canopies 156, and a second row 158, FIG. 5, of a pluralityof canopies 160 spaced below and offset from first row 154, and thirdand so on rows, such that water falls in cascade manner along thecanopies, as shown at arrows 161 in FIG. 5. The insert 150 has avertical wall 162 having a plurality of transfer openings 164therethrough, including a first row 166 of transfer openings 167 fromwhich first row 154 of canopies 156 extend horizontally as cantilevers,FIGS. 4, 9, and a second row 168 of transfer openings 169 from which thesecond row 158 of canopies 160 extend horizontally as cantilevers, andso on. In FIG. 5, canopies 153 extend out of the page toward the viewer.Insert 150 includes a horizontal wall 170 on the opposite side ofvertical wall 162 from canopies 153 and below transfer openings 164 suchthat water flow along the noted outlet flow path portion through outlet54 cascades along the canopies as shown at arrows 161 in FIG. 5, andthen some of the water flows through transfer openings 164 as shown atarrow 128 in FIG. 9 and then flows along horizontal wall 170. The waterflow thus steps down in staircase manner from canopies 153 to transferopenings 164 to horizontal wall 170. Horizontal wall 170 has a pluralityof discharge openings 172 therein discharging water therethrough back totank 26. Water which does not flow through discharge openings 172 willspill over the overflow edge lip 174 of wall 170. A plurality of shorttubular extensions 176 extend downwardly from horizontal wall 170 fromrespective discharge openings 172 and provide additional biologicalreactant surface area protrusions along the inner walls thereof. Thewater flow cascading at 161 along canopies 153 which does not flowthrough transfer openings 164 flows downwardly as shown at 132 in FIG. 9along sloped housing surface 178, and is discharged at outlet 54 beneathhorizontal wall 170 of insert 150. In normal operation, the primary flowpath is along sloped housing surface 178 as shown at arrow 132, and thewater flow path at 128, 130, 134 through the water polisher 150 is anauxiliary flow path. Removable insert 150 has the noted canopies 153,vertical wall 162, and horizontal wall 170. Insert 150 provides a waterpolisher grid further filtering and charging and aerating the water withextra oxygen creating additional biological filtration, and alsoproviding a quiet water return. The lower rows of canopies are ofdiffering horizontal cantilever length, for example as shown at 180,182, 184, FIG. 9, to accommodate sloped housing surface 178.

In the foregoing description, certain terms have been used for brevity,clearness, and understanding. No unnecessary limitations are to beimplied therefrom beyond the requirement of the prior art because suchterms are used for descriptive purposes and are intended to be broadlyconstrued. The different configurations, systems, and method stepsdescribed herein may be used alone or in combination with otherconfigurations, systems and method steps. It is to be expected thatvarious equivalents, alternatives and modifications are possible withinthe scope of the appended claims.

1. An aquarium filter assembly comprising a housing having mountingstructure for mounting to an aquarium tank, said tank having an interiorholding aquarium water therein, and an exterior, said tank having asidewall with a top, a filter cartridge in said housing, said filtercartridge having an upstream face and a downstream face, said housinghaving an inlet receiving dirty aquarium water, and an outlet returningclean filtered water to said tank, said housing defining a flow paththerethrough from upstream to downstream from said inlet to said outlet,a water pump in said housing pumping water along said flow path, saidhousing being an inverted U-shaped saddle having an upper bight at saidtoy of said sidewall of said tank, and having inner and outer legsdepending downwardly from said bight, said inner leg extending into saidinterior of said tank, said outer leg extending along said exterior ofsaid tank, said filter cartridge being in said outer leg, said waterpump being contained in said inner leg, said inner leg furthercomprising an interior channel wherein said water pump is configured forpumping water upwardly through said interior channel of said inner legand into said outer leg, wherein said housing has a filter chamberreceiving said filter cartridge therein, said filter cartridge dividingsaid filter chamber into a filter inlet plenum receiving water from saidinlet, and a filter outlet plenum delivering water to said outlet, saidupstream face of said filter cartridge facing said inlet plenum, saiddownstream face of said filter cartridge facing said filter outletplenum, said housing having a supply plenum supplying water to saidfilter inlet plenum from said water pump, said supply plenum having anoverflow bypass passage supplying water from said supply plenum to saidfilter outlet plenum and bypassing said filter cartridge in response toclogging of said filter cartridge causing a given rise of water level insaid housing.
 2. The aquarium filter assembly according to claim 1wherein said supply plenum spans said inner and outer legs, and saidhousing has a return plenum spanning said inner and outer legs andcrossing over said top of said sidewall of said tank and returning waterfrom said filter outlet plenum to said outlet, and wherein water fromsaid overflow bypass passage from said supply plenum joins with water insaid return plenum downstream of said downstream face of said filtercartridge.
 3. The aquarium filter assembly according to claim 2 whereinsaid supply plenum has a first cross-over portion directly above saidtop of said sidewall of said tank, said return plenum has a secondcross-over portion directly above said top of said sidewall of saidtank, said second cross-over portion has a lower wall guiding water flowtherealong, said second cross-over portion is laterally adjacent firstcross-over portion and has a plenum sidewall therebetween, said plenumsidewall extending from said lower wall of said second cross-overportion upwardly to said overflow bypass passage.
 4. An aquarium filterassembly comprising a housing having mounting structure for mounting toan aquarium tank, said tank having an interior holding aquarium watertherein, and an exterior, said tank having a sidewall with a top, afilter cartridge in said housing, said filter cartridge having anupstream face and a downstream face, said housing having an inletreceiving dirty aquarium water, and an outlet returning clean filteredwater to said tank, said housing defining a flow path therethrough fromupstream to downstream from said inlet to said outlet, a water pump insaid housing pumping water along said flow path, said housing being aninverted U-shaped saddle having an upper bight at said top of saidsidewall of said tank, and having inner and outer legs dependingdownwardly from said bight, said inner leg extending into said interiorof said tank, said outer leg extending along said exterior of said tank,said filter cartridge being in said outer leg, said water pump beingcontained in said inner leg, said inner leg further comprising aninterior channel wherein said water pump is configured for pumping waterupwardly through said interior channel of said inner leg and into saidouter leg, wherein said water pump is downwardly detachable from saidinner leg.
 5. An aquarium filter assembly comprising a housing havingmounting structure for mounting to an aquarium tank, said tank having aninterior holding aquarium water therein, and an exterior, said tankhaving a sidewall with a top, a filter cartridge in said housing, saidfilter cartridge having an upstream face and a downstream face, saidhousing having an inlet receiving dirty aquarium water, and an outletreturning clean filtered water to said tank, said housing defining aflow path therethrough from upstream to downstream from said inlet tosaid outlet, a water pump in said housing pumping water along said flowpath, said housing being an inverted U-shaped saddle having an upperbight at said top of said sidewall of said tank, and having inner andouter legs depending downwardly from said bight, said inner legextending into said interior of said tank, said outer leg extendingalong said exterior of said tank, said filter cartridge being in saidouter leg, said water pump being contained in said inner leg, said innerleg further comprising an interior channel wherein said water pump isconfigured for pumping water upwardly through said interior channel ofsaid inner leg and into said outer leg, wherein said water pump isdownwardly detachable from said inner leg via a living hinge springclip.
 6. An aquarium filter assembly comprising a housing havingmounting structure for mounting to an aquarium tank, said tank having aninterior holding aquarium water therein, and an exterior, said tankhaving a sidewall with a top, a filter cartridge in said housing, saidfilter cartridge having an upstream face and a downstream face, saidhousing having an inlet receiving dirty aquarium water, and an outletreturning clean filtered water to said tank, said housing defining aflow path therethrough from upstream to downstream from said inlet tosaid outlet, a water pump in said housing pumping water along said flowpath, said housing being an inverted U-shaped saddle having an upperbight at said top of said sidewall of said tank, and having inner andouter legs depending downwardly from said bight, said inner legextending into said interior of said tank and configured for extendingbelow water line, said outer leg extending along said exterior of saidtank, said filter cartridge being in said outer leg, said water pumpbeing contained in said inner leg, said inner leg further comprising aninterior channel wherein said water pump is configured for pumping waterupwardly through said interior channel of said inner leg and into saidouter leg, wherein said housing has a filter chamber receiving saidfilter cartridge therein, said filter cartridge dividing said filterchamber into a filter inlet plenum receiving water from said inlet, anda filter outlet plenum delivering water to said outlet, said upstreamface of said filter cartridge facing said inlet plenum, said downstreamface of said filter cartridge facing said filter outlet plenum, saidhousing having a supply plenum supplying water to said filter inletplenum from said water pump, said supply plenum having an overflowbypass passage supplying water from said supply plenum to said filteroutlet plenum and bypassing said filter cartridge in response toclogging of said filter cartridge causing a given rise of water level insaid housing.
 7. The aquarium filter assembly according to claim 6wherein said supply plenum spans said inner and outer legs, and saidhousing has a return plenum spanning said inner and outer legs andcrossing over said top of said sidewall of said tank and returning waterfrom said filter outlet plenum to said outlet, and wherein water fromsaid overflow bypass passage from said supply plenum joins with water insaid return plenum downstream of said downstream face of said filtercartridge.
 8. The aquarium filter assembly according to claim 7 whereinsaid supply plenum has a first cross-over portion directly above saidtop of said sidewall of said tank, said return plenum has a secondcross-over portion directly above said top of said sidewall of saidtank, said second cross-over portion has a lower wall guiding water flowtherealong, said second cross-over portion is laterally adjacent firstcross-over portion and has a plenum sidewall therebetween, said plenumsidewall extending from said lower wall of said second cross-overportion upwardly to said overflow bypass passage.
 9. An aquarium filterassembly comprising a housing having mounting structure for mounting toan aquarium tank, said tank having an interior holding aquarium watertherein, and an exterior, said tank having a sidewall with a top, afilter cartridge in said housing, said filter cartridge having anupstream face and a downstream face, said housing having an inletreceiving dirty aquarium water, and an outlet returning clean filteredwater to said tank, said housing defining a flow path therethrough fromupstream to downstream from said inlet to said outlet, a water pump insaid housing pumping water along said flow path, said housing being aninverted U-shaped saddle having an upper bight at said top of saidsidewall of said tank, and having inner and outer legs dependingdownwardly from said bight, said inner leg extending into said interiorof said tank and configured for extending below water line, said outerleg extending along said exterior of said tank, said filter cartridgebeing in said outer leg, said water pump being contained in said innerleg, said inner leg further comprising an interior channel wherein saidwater pump is configured for pumping water upwardly through saidinterior channel of said inner leg and into said outer leg, wherein saidwater pump is downwardly detachable from said inner leg.
 10. An aquariumfilter assembly comprising a housing having mounting structure formounting to an aquarium tank, said tank having an interior holdingaquarium water therein, and an exterior, said tank having a sidewallwith a top, a filter cartridge in said housing, said filter cartridgehaving an upstream face and a downstream face, said housing having aninlet receiving dirty aquarium water, and an outlet returning cleanfiltered water to said tank, said housing defining a flow paththerethrough from upstream to downstream from said inlet to said outlet,a water rump in said housing pumping water along said flow path, saidhousing being an inverted U-shaped saddle having an upper bight at saidtop of said sidewall of said tank, and having inner and outer legsdepending downwardly from said bight, said inner leg extending into saidinterior of said tank and configured for extending below water line,said outer leg extending along said exterior of said tank, said filtercartridge being in said outer leg, said water pump being contained insaid inner leg, said inner leg further comprising an interior channelwherein said water pump is configured for pumping water upwardly throughsaid interior channel of said inner leg and into said outer leg, whereinsaid water pump is downwardly detachable from said inner leg via aliving hinge spring clip.
 11. An aquarium filter assembly comprising ahousing having mounting structure for mounting to an aquarium tank, saidtank having an interior holding aquarium water therein, and an exterior,said tank having a sidewall with a top, a filter cartridge in saidhousing, said filter cartridge having an upstream face and a downstreamface, said housing having an inlet receiving dirty aquarium water, andan outlet returning clean filtered water to said tank, said housingdefining a flow path therethrough from upstream to downstream from saidinlet to said outlet, a water pump in said housing pumping water alongsaid flow path, said housing being an inverted U-shaped saddle having anupper bight at said top of said sidewall of said tank, and having innerand outer legs depending downwardly from said bight, said inner legextending into said interior of said tank said outer leg extending alongsaid exterior of said tank, said filter cartridge being in said outerleg, said water pump being contained in said inner leg, and said waterpump being downwardly detachable from said inner leg.
 12. The aquariumfilter assembly according to claim 11 wherein said housing has a filterchamber receiving said filter cartridge therein, said filter cartridgedividing said filter chamber into a filter inlet plenum receiving waterfrom said inlet, and a filter outlet plenum delivering water to saidoutlet, said upstream face of said filter cartridge facing said inletplenum, said downstream face of said filter cartridge facing said filteroutlet plenum, said housing having a supply plenum supplying water tosaid filter inlet plenum from said water pump, said supply plenum havingan overflow bypass passage supplying water from said supply plenum tosaid filter outlet plenum and bypassing said filter cartridge inresponse to clogging of said filter cartridge causing a given rise ofwater level in said housing.
 13. The aquarium filter assembly accordingto claim 12 wherein said supply plenum spans said inner and outer legs,and said housing has a return plenum spanning said inner and outer legsand crossing over said top of said sidewall of said tank and returningwater from said filter outlet plenum to said outlet, and wherein waterfrom said overflow bypass passage from said supply plenum joins withwater in said return plenum downstream of said downstream face of saidfilter cartridge.
 14. The aquarium filter assembly according to claim 13wherein said supply plenum has a first cross-over portion directly abovesaid top of said sidewall of said tank, said return plenum has a secondcross-over portion directly above said top of said sidewall of saidtank, said second cross-over portion has a lower wall guiding water flowtherealong, said second cross-over portion is laterally adjacent firstcross-over portion and has a plenum sidewall therebetween, said plenumsidewall extending from said lower wall of said second cross-overportion upwardly to said overflow bypass passage.
 15. The aquariumfilter assembly according to claim 11, wherein said water pump isdownwardly detachable from said inner leg via a living hinge springclip.
 16. The aquarium filter assembly according to claim 11, furthercomprising a removable top cover.